/*
 * Copyright (C) 2018 Drake, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.drake.channel

import androidx.lifecycle.Lifecycle
import androidx.lifecycle.LifecycleEventObserver
import androidx.lifecycle.LifecycleOwner
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.SupervisorJob
import kotlinx.coroutines.cancel
import kotlin.coroutines.CoroutineContext

/**
 * 异步协程作用域
 */
@PublishedApi
internal open class ChannelScope() : CoroutineScope {

    override val coroutineContext: CoroutineContext = Dispatchers.Main.immediate + SupervisorJob()

    constructor(
        lifecycleOwner: LifecycleOwner,
        lifeEvent: Lifecycle.Event = Lifecycle.Event.ON_DESTROY
    ) : this() {
        lifecycleOwner.lifecycle.addObserver(object : LifecycleEventObserver {
            override fun onStateChanged(source: LifecycleOwner, event: Lifecycle.Event) {
                if (lifeEvent == event) {
                    cancel()
                }
            }
        })
    }
}

